I try and avoid single use plastic, it seems obscene to me it even exists, but my waste ends up in landfill. To solve ocean plastic we need bin men and landfill in the countries causing it.
The fight against single use plastic in the developed world is just, but a separate issue.
A problem in the UK has been that plastics have been passed on for recycling only to be sent to China, for example, and dumped.
The issue as I see it is that we expect waste processing to be profitable and only do it if it is - waste processing should be handled from the profits of waste production.
So many companies conning their customers with half-empty packaging, products designed to break, etc., seems to be a large part of the problem.
I think it's become apparent that in pretty much every western country we were shipping them to China, as you described for the UK. That's now come to an end. Who DOES subsidise local industry enough to recycle in-country?